I feel kind of weird saying good things about Microsoft, but for better or worse, they have done a really impressive job about maintaining backward compatibilit

I feel kind of weird saying good things about Microsoft, but for better or worse, they have done a really impressive job about maintaining backward compatibility. Given the horrors their programmers must face in the name of this objective, I imagine they are not obsessed about it for its own sake, but because of legions of customers running badly written legacy applications they cannot or will not change, who will get very angry if Microsoft breaks their precious applications. Just remember the uproar when Service Pack 2 for Windows XP was released, where Microsoft deliberately broke compatibility to improve security.